A polarizing plate has been generally used for durability and water resistance as a structure where a protection film is laminated on one surface or both surfaces of a polarizer formed of a polyvinyl alcohol (hereinafter, referred to as ‘PVA’)-based resin generally dyed with a dichromatic dye or iodine by using an adhesive. In this case, as the adhesive used to attach the polarizer and the protection film, an aqueous adhesive formed of an aqueous solution of a polyvinyl alcohol-based resin has been mostly used. However, there is a problem in that adhesive strength of the aqueous adhesive is reduced according to a kind of material of the film, and in order to overcome this, a method of using a non-aqueous adhesive has been proposed. In this case, the non-aqueous adhesive may be divided into a heat-curable adhesive and a UV-curable adhesive.
Further, recently, for reduction in thickness and weight, a technology of applying a curable composition on one surface or both surfaces of the polarizer to form a transparent thin film layer has been proposed. In this case, the protection film is provided on one surface of the polarizer and the transparent thin film layer may be formed on an opposite surface thereto.
As described above, in the case of the adhesive composition or the composition forming the transparent thin film layer, in common, the UV-curable composition may be used. The UV-curable composition is a very useful material due to convenient workability and rapid curability in a process of manufacturing the polarizing plate. Meanwhile, in the related art, as the UV-curable composition, an acryl-based polymer or a methacryl-based polymer has been used. However, this UV-curable composition has a merit in terms of convenience due to a rapid curing speed, but there is a drawback in that due to this characteristic, as compared to thermosetting polymers and thermoplastic polymers, since a reaction is not performed for a sufficient time, a molecular weight is not relatively sufficiently increased, and thus it is difficult to embody a high modulus of elasticity and a high glass transition temperature.
Therefore, in order to overcome this drawback, there is a demand for a novel compound (monomer) providing a polymer which can embody a high storage modulus and a high glass transition temperature as compared to the UV-curable composition in the related art.